There are several types of dispensing devices or guns available for dispensing different types of flowable substance which are marketed in cartridges. One type of dispensing device is the grease gun which for the purposes of this specification and claims is defined as including a cylinder provided with a dispensing screw cap at a first end and a spring biased plunger at an opposite end. The screw dispensing cap is threadingly engaged with the first end of the cylinder and is provided with a lever operated piston valve. The spring biased plunger is biased so as to exert force in a direction from the opposite end toward the first end. The typical cartridge used for holding grease and for use with this grease gun is in the form of a tubular cartridge which is sealed at both ends by removable end plates and has a lip about one end of the cartridge. In use, the dispensing screw cap is unscrewed from the grease gun and the plunger pulled back as far as possible and held in place. The end plates of the grease cartridge are then removed and the cartridge dropped into the cylinder so that the lip rests on the first end of the cylinder. The dispensing screw cap is then screwed back onto the cylinder and the plunger released. The plunger pushes directly on the grease and travels inside the cartridge to force the grease toward the dispensing screw cap. Grease therefore passes into the screw cap and can be dispensed by actuation of the lever operated piston valve.
A second type of dispenser is the caulking gun which for the purposes of the specification and claims is defined as including a semicylindrical housing with a plate at one end for retaining a trigger actuated plunger and a plate at an opposite end provided with a radial extending recess. The caulking gun is typically used to dispense caulking and sealing compounds as well as adhesives which are supplied in cartridges in the form of hollow tubes having a moveable plate sealing one end of the tube and an integral wall at an opposite end. A nipple is form on the integral wall and has an external thread onto which a separate nozzle can be screwed. These cartridges are typical dropped into the housing of the caulking gun between the two plates so that the nipple extends through the radial recess and the plunger is located behind the moveable plate. By squeezing the trigger, the plunger can be advanced toward the nipple pushing on the moveable plate thereby forcing the compound out of the cartridge when the nipple has been cut or otherwise opened.
Another type of dispensing gun is the vacuum gun which for the purposes of this specification and claims is taken as including a lever actuated vacuum mechanism which is provided with a threaded opening for threadingly engaging a nipple of a cartridge holding a flowable substance. The cartridge is in substance identical to the cartridges described above in relation to chalking and sealing compounds and adhesives although often the thread on the nipple may be different. One brand of vacuum dispensing gun is the REINER.TM. grease gun. When using the vacuum gun, the nipple of the cartridge is cut and then simply screwed into the opening of the lever actuated vacuum mechanism. The lever (or in some cases levers) can then be pumped to create a vacuum which sucks the contents out of the cartridge through the cut nipple. In doing so, the moveable plate at the opposite end of the cartridge slides along an inside wall of the cartridge maintaining a seal.
Notwithstanding any similarities between the cartridges described above, they can not interchangeably be used with different types of dispensing devices. For example, the conventional grease cartridge cannot be used in a caulking gun or in a vacuum gun. Similarly, the cartridge used for caulking guns cannot be used in a conventional grease gun.